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Old 03-30-2011, 07:31 PM   #2821
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Not yet. I have been extremely busy trying to get ready for the WC. Right now there is not enough time in a day.

I will dyno the engines when I return from the race. I should have some results of the testing by the end of April. I have been doing lots of on track testing, and they are fast. Good on fuel too.
Dude I feel you, worlds prep is a pain and expensive I'm in no rush, you just get that 5 ready.
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Old 04-04-2011, 04:39 PM   #2822
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Default IFMAR 2011 1/8 I.C Circuit WC

We will be away racing, and supporting the Murnan Modified Motors team at the IFMAR 2011 1/8 I.C. Circuit World Championship. All orders placed from 4-4-2011 to 4-17-2011 will ship Monday April 18, 2011. Thanks.
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Old 04-12-2011, 10:44 AM   #2823
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I have a Murnan RBM3. Will the carb insert (01250-9tr505a) fit into a Novarossi carb. The original carb failed and I forgot to take out the insert before I tossed it.

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Old 04-12-2011, 08:04 PM   #2824
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Default 7604 in RBM3

can the nova 7604 rod fits the RBM3?
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Old 04-13-2011, 06:31 AM   #2825
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can the nova 7604 rod fits the RBM3?
I just ordered a P/S/R set for my Murnan RBM3 from Murnan. It uses the same set from the Nova 3sct. The Nova 3sct used a nova 07601 rod. So I would say no. I believe the 353 uses 7604 rod.


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Old 04-13-2011, 05:40 PM   #2826
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I have a Murnan RBM3. Will the carb insert (01250-9tr505a) fit into a Novarossi carb. The original carb failed and I forgot to take out the insert before I tossed it.

Pass you soon...
Yes. The insert will fit the standard novarossi carb. It will fit in most .12 carbs.
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Old 04-13-2011, 05:42 PM   #2827
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can the nova 7604 rod fits the RBM3?
No. That rod will hit the bottom of the block under high rpm use. The bottom of the rod is too big.
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Old 04-13-2011, 08:00 PM   #2828
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Yes. The insert will fit the standard novarossi carb. It will fit in most .12 carbs.
Thanks for the reply,, Good luck!!!!!
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Old 04-20-2011, 09:25 PM   #2829
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if u advance the timing of a motor by 1 degree, what would b the down side assuming it didnt work, and didnt work i mean not like u didnt do it right just wasnt good for the motor, would u loose bottom end or top or both or would it just do nothing.
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Old 04-21-2011, 05:21 AM   #2830
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if u advance the timing of a motor by 1 degree, what would b the down side assuming it didnt work, and didnt work i mean not like u didnt do it right just wasnt good for the motor, would u loose bottom end or top or both or would it just do nothing.
You would start to see a loss of bottom end, and throttle response. Are you cutting on your engines?
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Old 04-21-2011, 09:42 AM   #2831
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You would start to see a loss of bottom end, and throttle response. Are you cutting on your engines?

u got a pm
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Old 04-22-2011, 06:44 AM   #2832
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u got a pm
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Old 05-03-2011, 06:32 AM   #2833
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Uriah,

last weekend I ran one of your modded Kangaroos at a national event. The engine ran very well with laptimes that were comparaple to other top engines.

Now, after I disassembled the engine I found that the piston has a small "scratched" area on the exhaust side slightly below the brown ring of carbon build-up in the compression area. Those two grooves (oil-rings) are ground flat in this small area. Maybe the engine was a little bit lean....

What are my options here? The engine is still running fine and the sleeve looks good. Should I just continue to run, or buy a new unmodded Kangaroo to get cheap spare parts?
Would it be a good idea to take a new piston from another Kangaroo and break the "repaired" engine in again, or would it be better to change piston + sleeve and loose the benefits of the modded sleeve. In any case, the benefits of the Murnan cank would still make it a good engine....

Thanks for your feedback!

Best regards, Stefan
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Old 05-04-2011, 06:20 AM   #2834
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Uriah,

last weekend I ran one of your modded Kangaroos at a national event. The engine ran very well with laptimes that were comparaple to other top engines.

Now, after I disassembled the engine I found that the piston has a small "scratched" area on the exhaust side slightly below the brown ring of carbon build-up in the compression area. Those two grooves (oil-rings) are ground flat in this small area. Maybe the engine was a little bit lean....

What are my options here? The engine is still running fine and the sleeve looks good. Should I just continue to run, or buy a new unmodded Kangaroo to get cheap spare parts?
Would it be a good idea to take a new piston from another Kangaroo and break the "repaired" engine in again, or would it be better to change piston + sleeve and loose the benefits of the modded sleeve. In any case, the benefits of the Murnan cank would still make it a good engine....

Thanks for your feedback!

Best regards, Stefan
Hi. I'm sorry to hear about the piston problem. The Kangaroo has a microcast piston, and it is more likely to have a problem like that. I have seen that happen to them. I suspect that the engine was over revved before it was fully warmed up, or run too lean before it was fully broken in. I suggest that you replace the piston, and sleeve with a new one if possible. Usually when the piston gets scratched, the engine will not idle, and loses power.

You will still have more power than a stock Kangaroo with just the modified crank, but the modified piston, sleeve will make it even better for sure.

If you feel that the engine is running fine, you may want to continue to run it. Did the scratch damage the oil rings in the piston?
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Old 05-04-2011, 07:16 AM   #2835
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Hi Uriah,

thanks for your speedy follow-up, much appreciated. Yeah, the oil rings are polished (which means they are gone) in a small spot. At the very top, the piston is OK, the narrow brown ring is still there.
I will run the engine one more time and will monitor closely how it behaves. If it starts to act up, I will buy a new OEM Kangaroo and use the piston/sleeve set.

Thanks again and best regards, Stefan
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